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A/C contactor issue!! Need Help

A/C compressor/fan will not turn on.

Here's the confusing part:
- When main power is turned off, but control voltage is on, the contactor energizes and engages the contacts.
- As soon as the main power is turned on, the contactor disengages and will not send power to compressor/fan.
- If I manually engage the contactor, the compressor/fan turns on.
- I am consistantly getting about 27 volts at the control voltage side of contactor whether or not the main power is turned on.

Any ideas?
Is there an overload switch that is disengaging the contactor?

I'm sorry, the rules on site don't allow for specfic DIY instructions. Any competant HVAC tech will be able to fix you up.

I am not asking for DIY instructions. I am asking for a "professional opinion", which what this board is correct, "Ask a Professional." I am asking if the contactor is bad, possibly a short leading to the contactor, or if there is an overload switch that would apply in this situation. It doesn't seem that an overload switch would apply because I am consistantly getting about 27 volts on the control side of the contactor in all test situations.

Yes there is, but it doesn't cut off the power, as I can manually depress the contactor and the fan/compressor turn on.

Look on the side of the utility's box. It should say it has some kind of time delay. Put all the covers back on with the power off and then turn the power on. Wait five or more minutes. Unit should come on. If it is really hot out, you may have to wait longer. It's a load shedding device for the utility, after all.

Look on the side of the utility's box. It should say it has some kind of time delay. Put all the covers back on with the power off and then turn the power on. Wait five or more minutes. Unit should come on. If it is really hot out, you may have to wait longer. It's a load shedding device for the utility, after all.

Thank you so much for the professional response. That is exactly what it was! The voltage going in to the load shedding device was 27 v. and nothing coming out. Bypassed it and it works great. Going to call the electric company tomorrow.

Thank you so much for the professional response. That is exactly what it was! The voltage going in to the load shedding device was 27 v. and nothing coming out. Bypassed it and it works great. Going to call the electric company tomorrow.

You're right, it is. I just wasn't at the unit to test it at the time. The only reason I thought it wasn't us because it doesn't come on at all after the initial drop in power. Did some testing on the load shedding device and turns out that there was a short in the incoming 220 v line to the 24 v load shedding line. Assuming the load shedding device is blown. Gonna have the electric company come check it out.